超深层地震资料低频成像处理关键技术及其应用

Key techniques and their application of low-frequency imaging processing for ultra-deep seismic data

地震采集、处理和解释技术支撑超深层油气勘探开发不断取得重大进展,地震资料成像精度直接影响构造解释的效果。根据超深层地震资料具有信噪比低、主频低、频带窄等特点,提出了保护和恢复弱反射信号的低频成像处理思路。为了提高超深层地震资料的成像精度,开展了保护低频弱去噪处理、弱信号恢复及补偿、保持信噪比提高分辨率和子波一致性处理、剩余静校正和速度分析迭代处理、超低频叠前时间偏移处理等关键技术研究。以CS地区二维地震资料进行了实际应用,改善了超深层地震资料的品质和成像效果。

Seismic acquisition,processing and interpreting techniques support the continuous significant progress of ultra-deep oil and gas exploration and development,and the imaging accuracy of the seismic data directly affects the effects of structural interpretation.According to the characteristics of the ultra-deep seismic data,such as low signal-to-noise ratio,low dornunant frequency,narrow frequency band and so on,the idea of low-frequency imaging processing is proposed to protect and recover the weak reflection signals.In order to improve the imaging accuracy of the ultra-deep seismic data,some key techniques,including low-frequency protection and weak denoising processing,weak signal recovery and compensation,maintaining signal-to-noise ratio and improving resolution and wavelet consistency processing,residual static correction and velocity analysis iterative processing,ultra-low-frequency prestack time migration processing and so forth,are studied.The practical application of 2D seismic data in Area CS improves the quality and imaging effects of the ultra-deep seismic data.